Very first character I played (which I think the guy was using 1st Edition rules, maybe 2nd) was a pregen character the DM gave me, a Thief/Rogue.
In 2nd Edition I mainly DM'd, but in the few times I got to play I remember playing a Blade-Bard.
In 3rd/3.5 Edition I played a Fighter/Cleric/Barbarian in a home campaign, a Gunslinger in a D20 Modern home campaign, a Ranger/Rogue/Shadowdancer in a Return to the Temple of Elemental Evil Module. My primary Living Greyhawk characters were a Figher/Wizard/Spellsword and a Ranger/Druid/Beastmaster.
Now in 5th Edition, I have a Cleric/Fighter (Battlemaster) who I've spent the most time on, as well as a single game as a Warlock.
Of all the characters I think I had the most fun (mechanically) with the Shadowdancer, but my favorite character (RP-wise) overall was my Spellsword. Since it was Living Greyhawk, and I was going to conventions at the time, it was really awesome to sit down at a table of strangers in another state and have someone go, "I've heard about you!" as soon as I did my character introduction.